And john m



(No Model.)

W. H. MGGRATH & J. M. DRAM.

ELECTRIC METER.

No. 552,540. Patented- Jan. 7, 1896.

WITNESSES: gy lg Tgfzs: v 155M551 AN DREW lGRAHAM. PHOTD-LITKOWASHINGTUNJL UNTTE STATES PATENT OFFICE.

XVILLLUI ll. MCGRATH, OF FORT XVAYNE, INDIANA, AND JOHN M. ORAM, OF DALLAS, TEXAS.

ELECTRIC METER.

SPECIFICATION forming part of Letters Patent No. 552,540, dated January 7, 1896.

Application filed July 8, 1895. Serial No. 555,251. (No model.)

To (LZZ whom, it may concern:

Be it known that we,lVILLIAM H. MCGRATH, of Fort Wayne, in the county of Allen, State of Indiana, and JOHN M. ORAM, of Dallas, in the county of Dallas, State of Texas, citizens of the United States, have invented certain new and useful Improvements in Electric Meters, of which the following is a specification.

The object of our invention is to provide a simple and inexpensive apparatus for measuring and recording the time during which an electric translating device, such as a motor or light, is connected with the source of supply, such as a dynamo-electric machine, located at a central stat-ion.

Our improved meter is of so simple a construction and arrangement that its operation is clear to any ordinary intelligence and by its use we design to record the time that any translating device is in operation, while we avoid the disputes and the state of dissatis faction continually arising between the vendor and the vendee of electric current.

Our invention consists in the combination of an approximately accurate recording time indicator, such as a marine chronometer, having a train of graduated and numbered wheels, a switch or circuit-changer controlling the connection of the translating device with respect to the supply-circuit, and a mechanical connection between said switch and the escapement of the chronometer, so arranged that the operation of the switch to introduce the translating device with respect to the supplycircuitwill simultaneously start the chronomcter into operation, and the reverse movement of the switch will operate to cut out the said device and stop the chronometer or timerccording mechanism. The mechanical conneetion between the switch and the clock is a soft, resilient and delicate vibratory helical spring, and the switch is of the class which operates to break the circuit by a snap action to avoid arcing, while it also imparts the neccssary vibration to the mechanical connection between the switch and the timepiece. The arrangement of circuits preferred is such that the operation of the switch breaks a short circuit around the translating device to start said device into operation, and the closing of the short circuit operates to withdraw said device from the supply-circuit.

The accompanying drawing illustrates our invention.

is a chronometer or timepiece having a train of numbered wheels WV for recording or indicating their progression or movement. This timepiece has a balance-wheel 20, forming a part of its escapement.

D is a dynamo feeding a main circuit L, in which are electric-arc lights E in series; but any form of translating device may be sub stituted for the lights E, such as glow-lamps, motors, or heating devices.

S is a snap switch consisting of fixed springs 5 and 6. These are preferably of spring-brass. An arm 7, having curved ends, engages the upturned contact surfaces of springs 5 and 6. Arm 7 is on a bearing or arbor 30. A four-toothed ratchet-wheel 9 is fixed to arbor 30, upon which arm 7 is fixed.

A is an actuator-arm loosely journaled on arbor 30. A pawl a is pivoted at 19 on actuator-arm A, and a spring b 011 said arm holds pawl a in position.

The actuator A is capable of moving between its limit-stops n and m. A cord 0, fixed to A, furnishes asuitable means for operating said arm. The actuator A is retracted by a spring R. The switch S is operated bypulling the cord 0 until actuator A rests against its stop m. \Vhen this is done pawl a engages a tooth of ratchet 9 and rotates it one-quarter of a complete revolution, when the switcharm 7 engages with springs 5 and 6. Spring contact 5 is connected by conductor 20 to a point in circuit L on one side of the translating device E, and spring (3 is connected by conductor 21 to a point in L on the opposite side of E. It results from this that when 5 and (3 are electrically united by arm 7 the device E is cut out of circuit or short-cin cuited. Under these conditions when actuator A is operated a second time by pulling it from n to m the force necessarily exerted gradually increases as the curved ends of the arm 7 pass between the spring-contacts 5 and 6, and this force or pull continuing when the edges or corners of arm 7 are about to leave springs 5 and 3, the separation is completed by a sudden snap accompanying a movement of separation too rapid to permit the formation of an are between springs 5 and G on the one side and arm 7 on the other. This movement is, however, assisted and accelerated by the additional device now to be described.

F is a blade-spring fixed at point f. F carries at its upper end a delicate helical spring 8, having a curved mechanical contact-point located in the plane of rotation of the balance -wheel 20. Fixed upon arbor 30 is a double cam 8, preferably of insulating material, and this cam is in the plane of vibrating spring F and in position to engage with it.

The parts are shown. in a position such that the light E is in circuit, switch S being open, thus opening the short circuit 20 21, and the spring 3 is out of engagement with balancewheel 10, the recording time -pi.eee C being free to operate. If, now the cord 0 be pulled down so that actuator A strikes limit-stop m, arm 7 will connect 5 and 6, cutting E out, while cam S will engage spring F, forcing it toward the left, and spring 3 will engage balance-wheel w and stop the timepiece. The actuator A returns to its upper limit it under control of its retractor R. To again introduce E into circuit the actuatoris again pulled to its lower limit. Arm 7 leaves contact with 5 and 6 with a snap, assisted by spring F,-opcrating upon the cam 8, while spring F carries springs to the position shown. .5, engaging the wheel w, rotates it one-quarter revolution, thus certainly initiating the operation of the recording timepiece simultaneously with the starting of the light. It is to be noticed that this initial impulse or starting impulse is more certain and more prompt in its effect than the simple withdrawal of a block or obstruction to the operation of the time-recording device.

hat we claim, and desire to secure by Letters Patent, is

1. The combination of an electric circuit containing translating devices, a rotating switch for cutting said translating devices in and out of circuit, a recording time piece in cluding a motor driven train of wheels, a fiexible, vibratory spring having a free terminal in position to engage a wheel of said train, and a rotating cam mechanically connected to said switch, in position to engage said spring and force it into contact with a wheel when said cam is at one point of rotation and to release said spring upon a further movement, substantially as described.

The combination of a source of electrical supply, main conductors, translating devices, and a switch comprising a fixed terminal and a rotating terminal, a ratchet wheel fixed to said rotating terminal, a radial arm carrying a pawl taking into the teeth of the ratchet, a recording time piece including a train of wheels, a vibratory, flexible spring having a free terminal in position to engage a wheel of said time piece, and a cam connected to the rotating switch terminal in position to force said spring into engagement with the wheel when rotated into one position and to suddenly release said spring upon a continuation of said movement whereby the recording time piece is started and stopped by the rotation of the switch, substantially as described.

3. The combination of an electric circuit, translating devices therein, a motor driven train of wheels for indicating time, a flexible, vibratory spring having its free terminal in position to engage a wheel of the train, a rotating switch including an arbor bearing a cam shaped circuit terminal in position to engage a fixed terminal of the switch, a cam in position to engage said vibratory spring, a ratchet wheel, a spring retracted actuating arm carrying a pawl to engage said. ratchet, and suitable limit stops for said arm whereby the movement of the arm from one stop to the other operates the circuit closing cam to complete the branch circuit and the second. named cam to force the vibratory spring into engagement with a wheel of the train, substantially as described.

4. The combination of an electric circuit, translating devices therein, a motor driven train of wheels for indicating time, a flexible, vibratory spring in position to engage a wheel of the train, a rotating switch including an arbor bearing a cam shaped circuit terminal in position to engage a fixed terminal of the switch, a second cam in position to engage said vibratory spring, a ratchet wheel, an actuating arm carrying a pawl engaging said ratchet whereby the movement of said arm a predetermined distance completes the circuit and forces the vibratory spring into engagement with a wheel of the train and a repetition of the movement opens the circuit, releases the spring and imparts an initial impulse to the train of wheels, substantially as described WILLIAM ll. lilCGRNlil. JOHN M. ORAlil. i'itnesses:

E. T. Moonn, ll. A. Fannmc'rox. 

